Super sized stand-up Scooter project. Build thread

[Goped ESR750]

Done some more work on the chopped section of the frame.

Ground all the fittings off and shot blasted the paint off. Got to make bearing cups to fit the headstock, since I upgrading to taper roller bearings. The rest of the frame im getting custom made, its the only part of the project I will outsource, and only will be the bends in the basic frame, I may get him to make the rear axle up aswell.

Few pics of progress, and part compared like for like to the original.

[amberwolf]

Mmm....wish I had that pile of leftover parts.

Project looks interesting (but would probably be illegal to ride here in Phoenix/AZ).

[Goped ESR750]

Got the Etek motor through. Brand new and unused. Genuine Briggs and Stratton still got original box, ordered in 2004 never used. Seems genuine and was really cheap. Even cheaper than the T2 motor on my goped currently.

Took a few pics to compare the difference in size.

[def215]

wow. that sounds like a steal for less than a torkinator(if i recall they cost in the ballpark range of about 400-500 bucks). an etek on a giant standup scooter should be pretty interesting.

btw-i love the esr. i remember reading the build thread on the goped forum.

[Goped ESR750]

Thanks Def glad you like the ESR. Had alot of problems with the T2 on that build. Still not happy with the performance. Have restricted very heavily to protect motor best I can. Will never be sustainable.

This project I am hoping to cost less than the ESR project, the motor already cost less than the motor on the ESR. I paid £245 for the motor.

Currently stripped the brakes, no photos at the moment. The brakes are off to powder coat, getting them done black. Going to get new seals for them when I put them back together. Colour scheme is going to be same as ESR.

I will make the bearing cups as soon as the taper roller bearings I order arrive. I need to also machine the original loose bearing systems bottom race, so that is parallel to take a taper roller bearing.

Should be more pictures soon.

[Goped ESR750]

Completely stripped the front swing the weekend to prepare it for the tapered rollers. The bottom race of the loose bearings is part of a large block welded on and I am going to have to put the whole stem in the lathe to skim it parallel, will need a huge lathe, and have to make up a tool just to do it. That should not take long, the bearing cups will probably take longer.

Few problems with the front swing arm. Both bearings in the pivot and completely gone, did not actually have much of the needle rollers left, and some of the one I did I was able to snap it two in my hand. I can't get the bolt to come out of the swing arm. Going to try and press that out today. I think I am going to screw the washer up, but its very worn anyway by the look of it. It is supposed to run on the needle rollers but because on half of them where not in there seems to have worn down the washer instead.

I need to save the bolt though, I have been looking for replacement bearings. One of them is standard, but the needle roller is a very thin bearing something which I can't seem to source a replacement for. I think it must be a Peugeot specific part, they charge £53 for the replacement. I think I am going to have to bite the bullet on that one and replace it, the washer is only cheap. Bolt is £46 as well so if I can save that I would be happy.

The swing arm itself has got rust on the inside from a little hole at the base. I was thinking of drilling out and filling it back up with weld once I cleaned it, however I managed to source one that looks like its good condition on ebay for £5 so I gone for that instead. It is yet to arrive but it looks far better than what I got. If not, I am sure I can make good out the pair of them. Depends how well the bolt presses out of the arm though, could ruin it by doing that anyway.

Front suspension spring is little heavy for what I need I think. Seeing as I am loosing a lot of weight, looking to maybe replace with adjustable pit bike shock or something similar. The pitch is 265mm

Few pictures of where I am at.

[Goped ESR750]

Made bearings cups today. Did lovely little job. Pressed the races in, took it home. Was not until I tried offering the bearing to the race did I realise I made bit of an error. Not having used taper rollers before. I did not realise you need space behind the race for the bearing sit on the taper. I need to put the cups back in the lathe a cut a recess behind race. I am not sure if I really got enough material available though. I the wall thickness is about 5mm at the moment. I figure I could loose a few mm, but really by the look of it, I am thinking the bearing might need a full 5mm behind it. My races are press fitted into bearing cups, so going to try amend current cups. Might be the case of making a new set though. Should be great fun getting the races back out with damaging them too.

[Goped ESR750]

Been doing a little research on the bearings I bought. Managed to find the bearing diagram. I was trying to search how far the bearing protrudes from inner race, I was able to work this out for my bearing using the diagram.

http://cad.timken.com/image?cid=4845&plpver=10&categid=1048&prodid=1050&imgname=Tapered-Roller-Bearings---TS--Tapered-Single--2.JPG

On my bearing:

B= 20.63
T= 19.05

So it sticks out 1.58 mm... This is good news. I will shave two mm of the back of the bearing race, leaving me with at least a 3mm wall on the back stepped to 5mm everywhere else, except the wall inside the frame, which is about 2mm. I don't even need to clock it in, will just take a over cut as it is a clearance hole. Handy as I was making good progress and I hate having to make things twice.

[Goped ESR750]

Reworked the bearing cups giving a 2mm recess behind the race. Bearings now fit perfectly. Am very happy with the cups. These will now be powder coated black. Few pictures below.

[etard]

Very nice! That should be stout as hell! I do know that the 80's Honda scooters had a similar suspension setup to that of your's, I'm sure the Puegot handles much better as the Hondas seemed so soft to me. I'll be interested to see how this turns out, 60mph on a stand up seems a bit extreme, and on a hardtail nonetheless! Ypu should look into the front suspension design of formula one cars, you may be able to have a lever rising up from the swingarm that pushes the shock parallel to the frame as the wheel arches upwards, could even hide the shock inside the belly housing. There is also the "pull" type shock that pulls the shock against a stationary plate as the swingarm moves upward.

[Goped ESR750]

Thanks... Glad you like the project.

I was thinking the exact thing for a rear suspension. Having some sort of linkage to take the pivot motion of the swing and turn it into a linear motion to push against a shock in line with the frame.

This idea has been surpassed by my idea to copy goped's CIDLI design. Which using polurathane and a square inside another square ofset at 45... The internal square should only just be able to rotate inside the outer square. When the internal square is offset the little triangles which are around the edge are filled with poly. When the suspension pivots the inner square rotates into the poly which provides the suspension.

Here is link to image, as it did not embed well http://content.foto.mail.ru/mail/mak-zy/720/s-807.JPG

My design will change from this as in this design the poly is used to align the axis too. I would user bearings either side so the poly was just for suspension.

60mph is the goal, but definatly wont be riding around like that. Just needed a new project so I thought I would give it a go

[etard]

That's a very compact design and wil probably be real nice on the street. I just really prefer the feel and action of a coil, however, with space constraints that double square poly should be a win. I have a few curbside stand ups her and am watchin thus to get some pointers. There's definately a huge advantage to figuring out proper gear drive ratios with such a small rear wheel. I'll probably aim for a 40 mph top speed though. Be nice for stowing in the trunk ( boot) of a car. Do you plan in putting some sort if fairing on the steer stem and handlebars? Maybe a pod for instrumentation?

[Goped ESR750]

Yeah I definatly agree that in an ideal situation a spring and damper would be better, but I really think the linkage is probably a bit complicated and also may change the look drastically. No fairing, just straight pole. I intend for this too look like a go-ped as much as possible. Will probably have a small cluster though.

Did some work on suspension system today. Only roughing out a few sizes. Need to make bearing cups. The the race needs to be bigger than the inside of the square to allow the poly to be pressed in. It is 70mm. I have gone for 50mm ID 80mm OD tapered rollers. This way the race clears the square. I have machined a blank for one side with 70mm bore, got to machine a blank for the other side, when the bearings arrive I will machine the recess for the race.

Few pictures of my progress taken, but I will have to wait untill I am home to upload them. Pretty happy with the progress. I'm not very good with designing things. Do not have a computer graphics package, so I work from little notes and scraps. Often have to start making something to get an idea of where I am going, is certainly the case with this, am pretty happy with how its going though. Definatly think this is achievable.

Found out that this is also known as an indespension unit, used on trailers etc.

[Goped ESR750]

bearing cups blank looks huge. Thats because it is, I left it over sized until I finished machine. Should only be about 25mm... Is more like 40mm at the moment.

[Goped ESR750]

Feeling settled on a design, I looked up the dimension of the bearings I ordered and made both bearings cups today.

However, when I took them to the welder who I had spoken to a few days ago said he had thought about the design as well. He came up with a far better solution of securing the bearings cups. Unfortunately it involves making brand new cups, can never put the material back. The design is basically the same cup, but with a 10mm extension on the end with a slot milled in to take the square.

Grabbed two fresh lumps of 90mm stock and drilled 40mm clearance hole in both. Will work on them tomorrow. Bearings cups will be machine on lathe first, with three steps bored in. The extra steps is 60mm the size of the square stock. This should make the milling a lot quicker boring out the centre first. Hopefully should be able to get the two blanks ready for milling tomorrow, not sure if the actual milling will get done.

Few pictures below.

[Goped ESR750]

Finished the bearings blanks today ready for milling. Won't be able to do any machining over the weekend. This design certainly will be far stronger and look much better too. The last 10mm step of the bearing cup I bored to 60mm. Only have to open it up on the mill with a tool the same radius as what is on the box section.

The bearings arrived today as well. They look huge, I only got them this big because with the races pressed in, it gives my full access to the square which is 70mm. Shouldn't get any problems with them, pretty over engineered. I prefer to be safe rather than sorry.

[Goped ESR750]

offered up the headstock with the stem to see how it looks. It is quite a bit higher then it was originally. At least the length of the bearings cup. I could not fit the stem in the lathe to skim the step off, So I made a paralleled step to press on, it's not on yet. I am thinking of grinding the welds off, machining it.. The get it welded again. Think I will have to make a jig to ensure it goes back the same.

I need to get the bearing cup as close as possible though. Will need to cut some of the tube down anyway.

Here is few pictures of where I am at.

[Goped ESR750]

Finally got the bearings cups finished for the CIDLI today. Which was handy as this is the day I had set out to see the guy who is going to weld this for me. I am seeing a custom harley fabricator, who makes all sorts of big bike frames from scratch. So I am getting him to sort the frame welded to the original section I have and then a bend and then weld to the CIDLI knuckle.

Sample block of polyurethane arrived today. I got a 70A shore rating 25x25mm block. I am going to test it a bit, but I am thinking this should be an ideal rating. It bends easy but under compression is good. I am going to see how it reacts with different loadings in a manual and hydraulic press. Manual for rebound shock loading and use the hydraulic press to dump 30 tonnes on it to see what it does.

Probably use rods as opposed to block when it comes to it. am undecided yet. Look forward to getting a rolling frame sorted though.

[Goped ESR750]

Got my callipers back from the powder coaters, and rebuilt them.

Got 15mm rods of poly to use for suspensions, these seem like they will work. Cant quite push them all the way in by hand which is what I needed. Will lubricate them and press them in.

Few pics of where I am at.

[Goped ESR750]

Pressed the polyurethane rods into the square. This was not an easy task, I used Vaseline to lubricate them. I ended up using cables ties covering most of the exposed poly whilst pressing it in. This stopped the rods bending out. This is just a test as the rods will have to come out before welding and powder coating. I am going to have to make a tool to get them back in the box section once it is welded to the frame.

I can see getting the rod in to them made frame is probably going to be a bit difficult.

The second picture is with my mate with all his weight on a spanner driving the inner square. Was able to spin it when used a huge 3m leverage. I think this should be about right. I might go up a grade or use a back stop to ensure it never spins out. Trail and error really have to idea how it is going to work out, but is looking good though.

Cut my front suspension in half. Needed to cut it down to fit in the lathe to skim the old bearing step off. Two blocks where welded on to position it when it goes back.

Few pictures of where I am at.

[Goped ESR750]

Got the front suspension parts welded back together today, they where welded all across the joint instead of the two slugs that where on there before. This should make it a little stronger. Also made a good start on the shaft for the suspension.

The shaft is about 350 long at the moment, the first section on the larger end is for the swing arm to be welded too. As I am not fabricating the swing arm I have left this oversized at 100mm long so the custom builder can tell me how he wants it.

Managed to get two of the sides milled, but ran out of time. Will finish the square tomorrow; this is the part which will drive the inner square on the suspension.

Few pics of where I'm at.

[John in CR]

Looking good Goped. Have you done a rear suspension like that before, or otherwise have experience with the square-in-a-square plus elastimer suspension? I was wondering how you came up with a starting point for sizing and the elastic part.

[Goped ESR750]

Looking good Goped. Have you done a rear suspension like that before, or otherwise have experience with the square-in-a-square plus elastimer suspension? I was wondering how you came up with a starting point for sizing and the elastic part.

Thanks. No, I have not made anything like this before. I needed a compact suspension system, without a shock absorber above the wheel. Goped produce a stand up with a similar far smaller suspension with no bearings. I found out the materials it was made from and sourced my own. I'm not even sure if it will work yet. The sizing just seemed reasonable in relation to the wheel width, and the tubing on the frame.

This is all trail an error. I have ordered the next grade harder rod to see the difference. I have real concerns of spinning the inner square. Under large load I have been able to spin it, but I really don't know what load I am going to get in normal use. Also having the ends capped off will stop the poly compressing out the end which will stiffen it up too. I really prefer to be safe rather than sorry so needs some fine tuning I think.

[zzoing]

Ok everybody... watch and learn... 8-}.....

I have a Speedfight 2!!!! the wheel is pretty heavy but pretty satisfyling to navigate in the dust and fields with... I ended up taking some wrong turns on mine, going down a ravine and having to go up again, juddering through corn fields that were felt like a rodeo ride, and getting lost in some wet muddy woods that i thought were 1 km wide but in fact were about 10 kilometers... it has very good handling.

But WHAT is this thing? with the rubber? the back axle goes through the square area? a kind of schematic sketch on paper would have helped me figure out what is happening at the back of that scooter!

how many inches of suspension are happening at the back? depends if you off road, but for general purpose, maybe 2-3 inches makes a more controlled and comfy ride if there are bumps. What would have sprung to my mind is a pivot with a coil or leaf suspension, maybe even some air suspension like a tennis ball or a larger volume of polyurethane.

I was amazed that you stripped that bike totally, i thought you would put the battery in the saddle and take off all but the frame and the excellent outer shell on the speedfight. really i would have kept the back suspension!!! Piolini!!! it rocks! Oh my god.

amazing tools and engineering!

[Goped ESR750]

Ok everybody... watch and learn... 8-}.....

I have a Speedfight 2!!!! the wheel is pretty heavy but pretty satisfyling to navigate in the dust and fields with... I ended up taking some wrong turns on mine, going down a ravine and having to go up again, juddering through corn fields that were felt like a rodeo ride, and getting lost in some wet muddy woods that i thought were 1 km wide but in fact were about 10 kilometers... it has very good handling.

But WHAT is this thing? with the rubber? the back axle goes through the square area? a kind of schematic sketch on paper would have helped me figure out what is happening at the back of that scooter!

how many inches of suspension are happening at the back? depends if you off road, but for general purpose, maybe 2-3 inches makes a more controlled and comfy ride if there are bumps. What would have sprung to my mind is a pivot with a coil or leaf suspension, maybe even some air suspension like a tennis ball or a larger volume of polyurethane.

I was amazed that you stripped that bike totally, i thought you would put the battery in the saddle and take off all but the frame and the excellent outer shell on the speedfight. really i would have kept the back suspension!!! Piolini!!! it rocks! Oh my god.

amazing tools and engineering!

Thanks for checking zzoing. Not really sure of the suspension travel on the rear wheel at the moment, the longer the swing arm the greater the travel. Thee inner square pivots just under 45 degrees before it spins out, so the maximum travel ideal would be about 30 degrees. I am still fine tuning the fill material, it will work but I am not happy with it at the moment.

It is very similar to trailer suspension known as Indespension. I chose this sort of system as the point of compression is around the pivot point; surely the most compact system possible. A spring with a damper would of been better, but this thing is more of a toy and I want it too look right. With a spring above the rear wheel will take away from the look of the stand-up.